Photovoltaic self-consumption in buildings : A review

Battery energy storage systems have gained increasing interest for serving grid support in various application tasks. In particular, systems based on lithium-ion batteries have evolved rapidly with a wide range of cell technologies and system architectures available on the market. On the application side, different tasks for storage deployment demand distinct properties of the storage system. This review aims to serve as a guideline for best choice of battery technology, system design and operation for lithium-ion based storage systems to match a specific system application. Starting with an overview to lithium-ion battery technologies and their characteristics with respect to performance and aging, the storage system design is analyzed in detail based on an evaluation of real-world projects. Typical storage system applications are grouped and classified with respect to the challenges posed to the battery system. Publicly available modeling tools for technical and economic analysis are presented. A brief analysis of optimization approaches aims to point out challenges and potential solution techniques for system sizing, positioning and dispatch operation. For all areas reviewed herein, expected improvements and possible future developments are highlighted. In order to extract the full potential of stationary battery storage systems and to enable increased profitability of systems, future research should aim to a holistic system level approach combining not only performance tuning on a battery cell level and careful analysis of the application requirements, but also consider a proper selection of storage sub-components as well as an optimized system operation strategy.

https://www.mdpi.com/1996-1073/10/12/2107/pdf

Lithium-Ion Battery Storage for the Grid—A Review of Stationary Battery Storage System Design Tailored for Applications in Modern Power Grids

Peer-to-peer energy sharing through a two-stage aggregated battery control in a community Microgrid

https://onlinelibrary.wiley.com/doi/epdf/10.1002/pip.3189

Impact of weighted average cost of capital, capital expenditure, and other parameters on future utility-scale PV levelised cost of electricity

Given the increasing penetration of renewable energy technologies as distributed generation embedded in the consumption centres, there is growing interest in energy storage systems located very close to consumers. These systems allow to increase the amount of renewable energy generation consumed locally, they provide opportunities for demand-side management and help to decarbonise the electricity, heating and transport sectors. 

In this paper, the authors present an interdisciplinary review of community energy storage (CES) with a focus on its potential role and challenges as a key element within the wider energy system. The discussion includes: the whole spectrum of applications and technologies with a strong emphasis on end user applications; techno-economic, environmental and social assessments of CES; and an outlook on CES from the customer, utility company and policy-maker perspectives. Currently, in general only traditional thermal storage with water tanks is economically viable. However, CES is expected to offer new opportunities for the energy transition since the community scale introduces several advantages for electrochemical technologies such as batteries. Technical and economic benefits over energy storage in single dwellings are driven by enhanced performance due to less spiky community demand profile and economies of scale respectively. In addition, CES brings new opportunities for citizen participation within communities and helps to increase awareness of energy consumption and environmental impacts.

/pdf/an-interdisciplinary-review-of-energy-storage-for-jybnp7b7rj.pdf

An interdisciplinary review of energy storage for communities: Challenges and perspectives

Sizing of Residential PV Battery Systems

Sizing of Battery Converters for Residential PV Storage Systems

This paper investigates the profitability of PV battery systems that aim to reduce the electricity purchased from the grid of households. The economic feasibility is assessed based on the approach of calculating the mean electricity cost of the household equipped with a PV battery system. The study focuses on the main question: What is the break-even point of the battery system price at which residential PV battery systems become economically viable in Germany? This is analyzed by determining the limit of profitability in terms of required battery system price, which makes the investment in a PV battery system under given circumstances profitable. The impact of different economic input parameters on the required battery system price was studied for a defined reference case. The results reveal that the major factor is the interest rate, followed by the PV system price, retail electricity price and feed-in tariff. Nevertheless, several uncertainties with regard to the economic assessment exist. However, assuming that the calculated required battery prices will be achieved in the future; investing in a PV battery system is financially more attractive than purchasing the entire electricity demand from the grid.

/pdf/economics-of-residential-pv-battery-systems-in-the-self-k9c0br7ctw.pdf

Economics of Residential PV Battery Systems in the Self-Consumption Age

Considering the challenges of grid integration, battery systems could be used to smooth the infeed of PV systems. This paper presents autonomous forecast-based operation strategies for residential PV battery systems that can be used to improve grid integration of PV systems. Simulation calculations on a timescale of one minute were performed to determine the impact of error-prone forecasts of the PV generation and load demand. Like load forecasts which need to be calculated on-site, also PV forecasts can be autonomously derived from measurements to avoid costs from forecast services. For the purpose of dealing with forecast errors a model predictive controller is implemented which can compensate the essential undesired effects of forecast errors. In this paper basic forecast approaches were assessed to show that even simple prediction models result in an economic feasible and autonomous grid relieving operation of residential PV battery systems.

/pdf/feed-in-power-limitation-of-grid-connected-pv-battery-85ikznza1r.pdf

Feed-in Power Limitation of Grid-Connected PV Battery Systems with Autonomous Forecast-Based Operation Strategies

Battery energy storage devices coupled with photovoltaic (PV) systems have to react to the fluctuating nature of the PV output and electrical demand in residential buildings. However, the charging and discharging power cannot be adjusted to the power fluctuations without any time delay so that an inherent temporal mismatch between the battery power and the residual power (PV output minus load) occurs under dynamic conditions. This paper presents a simulation study analyzing the response time-induced mismatch losses of grid-connected PV-battery systems. Firstly, the response time issue is analyzed theoretically to reveal how the energy flows between the household and the grid are changed due to the delayed battery response. Then, measurements are presented to show the dynamic behavior of two different PV-battery systems. The experimental results reveal settling times of up to 7 s to reach the steady state after an abrupt step change in the load demand. Thirdly, simulations of an AC-coupled PV-battery system are carried out with a time step size of 1 s. A sensitivity analysis is conducted to identify the impact of the dynamic response on the annual amount of energy exchanged with the grid. It is found that longer response times are accomplished by an increase in the grid feed-in and grid supply as well. Consequently, a slow-reacting battery system diminishes the economic benefit for the owner of the PV-battery system. In order to improve the transparency from the end-customeŕs point of view, response time-related specifications should be stated in the data sheets of the products in the future.

J. Weniger

Papers

Sizing of Residential PV Battery Systems

Sizing of Battery Converters for Residential PV Storage Systems

Economics of Residential PV Battery Systems in the Self-Consumption Age

Feed-in Power Limitation of Grid-Connected PV Battery Systems with Autonomous Forecast-Based Operation Strategies

Dynamic mismatch losses of grid-connected PV-battery systems in residential buildings